The present invention relates to an image forming apparatus and an image forming system incorporating the same.
An image forming apparatus, such as a laser beam printer, has already been well known. Such an image forming apparatus comprises, for example, an image carrier for carrying a latent image thereon; developing devices, each of which develops the latent image carried on the image carrier with use of a developing agent; a rotary member having a plurality of loading sections arranged in a circumferential direction thereof and allowing removable loading of the developing devices; and a motor for rotating the rotary member. The image forming apparatus can perform image forming operation with a single developing device loaded in one of the loading sections.
When an image signal is transmitted from an external apparatus, such as a host computer, to the image forming apparatus, the rotary member situated at a home position, where the rotary member awaits execution of image forming operation, is rotated by driving force of the motor, so that the developing device is placed at the development position opposing the image carrier. The latent image carried on the image carrier is developed with the developing agent stored in the developing device, to thus form a visible image, and the visible image is transferred onto a medium, thereby eventually forming an image. Such an image forming apparatus is disclosed in Japanese Patent Publication No. 2005-24859A, for example.
When the developing device remains loaded only in one of the plurality of loading sections, the distribution of load (weight) of the rotary member becomes uneven, to thus bring imbalance to the rotary member. Therefore, when the rotary member is situated at the home position, there may arise a case where the rotary member becomes displaced (rotated) under the own weight of the developing device, depending on the position of the one loading section to which the developing device is loaded. In a case where an impact is inflicted on the rotary member when the rotary member is situated at the home position, the rotary member is displaced (rotated) by the impact.
In order to prevent displacement of the rotary member, the related-art printer is equipped with a stopper which comes in contact with the rotary member situated in the home position. However, in order to cause the stopper to duly exhibit its function, the strength of the stopper must be sufficiently ensured.